Fluid-filled chamber with a tensile element

ABSTRACT

A fluid-filled chamber, which may be incorporated into articles of footwear and other products, may include an outer barrier and a tensile element. The outer barrier may have a first portion, an opposite second portion, and an interior surface defining an interior void. The tensile element may be secured to the first portion of the outer barrier in a plurality of first bond areas and may be secured to the second portion of the outer barrier in a plurality of second bond areas. Each of the bond areas may be connected to portions of the tensile element spaced from the interior surface.

BACKGROUND

Articles of footwear generally include two primary elements, an upperand a sole structure. The upper is formed from a variety of materialelements (e.g., textiles, foam, leather, and synthetic leather) that arestitched or adhesively bonded together to form a void on the interior ofthe footwear for comfortably and securely receiving a foot. An ankleopening through the material elements provides access to the void,thereby facilitating entry and removal of the foot from the void. Inaddition, a lace is utilized to modify the dimensions of the void andsecure the foot within the void.

The sole structure is located adjacent to a lower portion of the upperand is generally positioned between the foot and the ground. In manyarticles of footwear, including athletic footwear, the sole structuregenerally incorporates an insole, a midsole, and an outsole. The insole,which may be located within the void and adjacent to a lower surface ofthe void, is a thin compressible member that enhances footwear comfort.The midsole, which may be secured to a lower surface of the upper andextends downward from the upper, forms a middle layer of the solestructure. In addition to attenuating ground reaction forces (i.e.,providing cushioning for the foot), the midsole may limit foot motionsor impart stability, for example. The outsole, which may be secured to alower surface of the midsole, forms at least part of theground-contacting portion of the footwear and is usually fashioned froma durable and wear-resistant material that includes texturing to improvetraction.

Generally, the midsole is primarily formed from a foamed polymermaterial, such as polyurethane or ethylvinylacetate, that extendsthroughout a length and width of the footwear. In some articles offootwear, the midsole may include a variety of additional footwearelements that enhance the comfort or performance of the footwear,including plates, moderators, fluid-filled chambers, lasting elements,or motion control members. In some configurations, any of theseadditional footwear elements may be located between the midsole andeither of the upper and the outsole, may be embedded within the midsole,or may be encapsulated by the foamed polymer material of the midsole,for example. Although many midsoles are primarily formed from a foamedpolymer material, fluid-filled chambers or other non-foam structures mayform part of or a majority of some midsole configurations.

Various techniques may be utilized to form fluid-filled chambers forarticles of footwear or other products, including a two-film technique,a thermoforming technique, and a blowmolding technique, for example. Inthe two-film technique, two separate polymer sheets are bonded togetherat specific locations. The thermoforming technique is similar to thetwo-film technique in that two polymer sheets are bonded together, butalso includes utilizing a heated mold to form or otherwise shape thepolymer sheets. In the blow-molding technique, a parison formed from amolten or otherwise softened polymer material is placed within a moldhaving a cavity with the desired configuration of the chamber.Pressurized air induces the polymer material to conform to surfaces ofthe cavity. The polymer material then cools and retains the shape of thecavity, thereby forming the chamber.

Following each of the techniques discussed above, the chambers arepressurized. That is, a pressurized fluid is injected into the chambersand then sealed within the chambers. One method of pressurizationinvolves forming inflation conduits in residual portions of the polymersheets or the parison. In order to pressurize the chambers, the fluid isinjected through the inflation conduits, which are then sealed. Theresidual portions of the polymer sheets or the parison, including theinflation conduits, are then trimmed or otherwise removed tosubstantially complete manufacture of the chambers.

SUMMARY

Various features of fluid-filled chambers and methods of manufacturingfluid-filled chambers are disclosed below. In one configuration, Afluid-filled chamber comprises a barrier and a tensile element. Thebarrier is formed of a polymer material that defines an interior voidand has a first portion, a second portion, and a sidewall portion. Thefirst portion forms a first surface of the chamber. The second portionis located opposite the first portion and forms a second surface of thechamber. The sidewall portion that extends between the first portion andthe second portion to form a sidewall surface of the chamber. Thetensile element is located within the interior void. The tensile elementis spaced inward from the sidewall portion. The tensile element is (a)secured to the first portion of the barrier in a plurality of discretefirst bond areas and (b) secured to the second portion of the barrier ina plurality of discrete second bond areas. Each of the first bond areasand second bond areas is substantially surrounded by unbonded portionsof the tensile element.

In another configuration, a fluid-filled chamber comprises a barrier anda tensile layer. The barrier is formed of a polymer material thatdefines an interior void and has a first portion, a second portion, anda sidewall portion. The first portion forms a first surface of thechamber. The second portion is located opposite the first portion andforms a second surface of the chamber. The sidewall portion extendsbetween the first portion and the second portion to form a sidewallsurface of the chamber. The tensile layer is located within the interiorvoid. The tensile layer is spaced inward from the sidewall portion. Thetensile layer has a length, a width, and a configuration of a sheet thatis secured to (a) the first portion of the barrier in a plurality offirst bond areas and (b) the second portion of the barrier in aplurality of second bond areas. Each of the first bond areas and secondbond areas is spaced from the other first bond areas and second bondareas along both the length and the width of the tensile layer.

In a further configuration, a fluid-filled chamber comprises a barrier,a bond inhibitor, a tensile layer, and a fluid. The barrier is formed ofa polymer material that defines an interior void. The bond inhibitor islocated adjacent to an inner surface of the barrier and has a pluralityof apertures. The tensile layer is located within the interior void. Thetensile layer is spaced inward from a periphery of the barrier. Thetensile layer has a configuration of a sheet extending through theplurality of apertures, being secured to the barrier at a plurality ofbonded areas, and having an unbonded area substantially surrounding eachof bonded areas. The fluid is located within the interior void and ispressurized to place the unbonded area of the tensile element intension.

In yet another configuration, a method of manufacturing an article offootwear comprises steps of locating, compressing, bonding,pressurizing, and incorporating. In one step, the method includeslocating a first polymer layer, a second polymer layer, and a tensilelayer between two mold portions. The tensile layer is positioned betweenthe first polymer layer and the second polymer layer. In another step,the method includes compressing the first polymer layer, the secondpolymer layer, and the tensile layer between the mold portions to form aplurality of discrete and spaced bonds between the tensile layer andeach of the first polymer layer and the second polymer layer. In anotherstep, the method includes bonding the first polymer layer to the secondpolymer layer around a periphery spaced from the tensile layer to forman interior void. In another step, the method includes pressurizing theinterior void to space areas of the tensile layer located between thebonds from the first polymer layer and the second polymer layer. Inanother step, the method includes incorporating the chamber into a solestructure of the article of footwear.

The advantages and features of novelty characterizing aspects of theinvention are pointed out with particularity in the appended claims. Togain an improved understanding of the advantages and features ofnovelty, however, reference may be made to the following descriptivematter and accompanying figures that describe and illustrate variousconfigurations and concepts related to the invention.

FIGURE DESCRIPTIONS

The foregoing Summary and the following Detailed Description will bebetter understood when read in conjunction with the accompanyingfigures.

FIG. 1 is a lateral side elevational view of an article of footwear.

FIGS. 2A-2B are a cross-sectional views of the article of footwear, asdefined by section lines 2A and 2B in FIG. 1.

FIG. 3 is a perspective view of a fluid-filled chamber from the articleof footwear.

FIG. 4 is an exploded perspective view of the chamber.

FIG. 5 is a top plan view of the chamber.

FIG. 6 is a bottom plan view of the chamber.

FIG. 7 is a lateral side elevational view of the chamber.

FIGS. 8A-8C are a cross-sectional views of the chamber, as defined bysection lines 8A through 8C in FIG. 5.

FIG. 9 is a perspective view of a mold that may be utilized in a processfor manufacturing the chamber.

FIGS. 10A-10D are perspective views of the mold depicting steps in theprocess for manufacturing the chamber.

FIGS. 11A-11D are schematic cross-sectional views of the mold, asrespectively defined by section lines 11A-11D in FIGS. 10A-10D.

FIGS. 12A-12G are top plan views corresponding with FIG. 5 and depictingfurther configurations of the chamber.

FIG. 13 is a bottom plan view corresponding with FIG. 6 and depicting afurther configuration of the chamber.

FIGS. 14A and 14B are cross-sectional views corresponding with FIG. 8Aand depicting further configurations of the chamber.

FIG. 15 is a cross-sectional view corresponding with FIG. 8C anddepicting a further configuration of the chamber.

FIG. 16 is a partial cross-sectional perspective view of a furtherconfiguration of the chamber.

FIG. 17 is a top plan view corresponding with FIG. 5 and depicting thefurther configuration of the chamber of FIG. 16.

FIG. 18 is a bottom plan view corresponding with FIG. 6 and depictingthe further configuration of the chamber of FIG. 16.

FIGS. 19A and 19B are cross-sectional views of the further configurationof the chamber of FIG. 16, as defined by section lines 19A and 19B inFIG. 17.

DETAILED DESCRIPTION

The following discussion and accompanying figures disclose variousconfigurations of fluid-filled chambers and methods for manufacturingthe chambers. Although the chambers are disclosed with reference tofootwear having a configuration that is suitable for running, conceptsassociated with the chambers may be applied to a wide range of athleticfootwear styles, including basketball shoes, cross-training shoes,football shoes, golf shoes, hiking shoes and boots, ski and snowboardingboots, soccer shoes, tennis shoes, and walking shoes, for example.Concepts associated with the chambers may also be utilized with footwearstyles that are generally considered to be non-athletic, including dressshoes, loafers, and sandals. In addition to footwear, the chambers maybe incorporated into other types of apparel and athletic equipment,including helmets, gloves, and protective padding for sports such asfootball and hockey. Similar chambers may also be incorporated intocushions and other compressible structures utilized in household goodsand industrial products. Accordingly, chambers incorporating theconcepts disclosed herein may be utilized with a variety of products.

General Footwear Structure

An article of footwear 10 is depicted in FIGS. 1-2B as including anupper 20 and a sole structure 30. For reference purposes, footwear 10may be divided into three general regions: a forefoot region 11, amidfoot region 12, and a heel region 13. Forefoot region 11 generallyincludes portions of footwear 10 corresponding with the toes and thejoints connecting the metatarsals with the phalanges. Midfoot region 12generally includes portions of footwear 10 corresponding with the archarea of the foot. Heel region 13 generally includes portions of footwear10 corresponding with rear portions of the foot, including the calcaneusbone. Regions 11-13 are not intended to demarcate precise areas offootwear 10. Rather, regions 11-13 are intended to represent generalareas of footwear 10 to aid in the following discussion. In addition tobeing applied to footwear 10, regions 11-13 may also be applied to upper20, sole structure 30, and individual elements thereof.

Footwear 10 also includes a lateral side 14 and a medial side 15. Moreparticularly, lateral side 14 corresponds with an outside area of thefoot (i.e. the surface that faces away from the other foot), and medialside 15 corresponds with an inside area of the foot (i.e., the surfacethat faces toward the other foot). Lateral side 14 and medial side 15also extend through each of regions 11-13 and correspond with oppositesides of footwear 10. As with regions 11-13, sides 14 and 15 representgeneral areas of footwear 10 to aid in the following discussion, and mayalso be applied to upper 20, sole structure 30, and individual elementsthereof in addition to being applied to footwear 10.

Upper 20 is depicted as having a substantially conventionalconfiguration incorporating a plurality of material elements (e.g.,textile, foam, leather, and synthetic leather) that are stitched,adhered, bonded, or otherwise joined together to form an interior voidfor securely and comfortably receiving a foot. The material elements maybe selected and located with respect to upper 20 in order to selectivelyimpart various properties to upper 20, such as durability,air-permeability, wear-resistance, flexibility, and comfort. An ankleopening 21 in heel region 13 provides access to the interior void. Inaddition, upper 20 may include a lace 22 that is utilized in aconventional manner to modify the dimensions of the interior void,thereby securing the foot within the interior void and facilitatingentry and removal of the foot from the interior void. Lace 22 may extendthrough apertures in upper 20, and a tongue portion of upper 20 mayextend between the interior void and lace 22. Upper 20 may alsoincorporate a sockliner 23 that is located within the void in upper 20and adjacent a plantar (i.e., lower) surface of the foot to enhance thecomfort of footwear 10. Given that various aspects of the presentapplication primarily relate to sole structure 30, upper 20 may exhibitthe general configuration discussed above or the general configurationof practically any other conventional or non-conventional upper.Accordingly, the overall structure of upper 20 may vary significantly.

Sole structure 30 is secured to upper 20 and has a configuration thatextends between upper 20 and the ground. In effect, therefore, solestructure 30 is located to extend between the foot and the ground. Inaddition to attenuating ground reaction forces (such as by providingcushioning for the foot), sole structure 30 may provide traction, impartstability, and limit various foot motions, such as pronation.

The primary elements of sole structure 30 are a midsole 31 and anoutsole 32. Midsole 31 may incorporate a polymer foam material, such aspolyurethane or ethylvinylacetate. Midsole 31 may also incorporate afluid-filled chamber 33. In addition to the polymer foam material andchamber 33, midsole 31 may incorporate one or more other footwearelements that enhance the comfort, performance, or ground reaction forceattenuation properties of footwear 10, including plates, moderators,lasting elements, or motion control members.

Outsole 32, which may be absent in some configurations of footwear 10,is depicted as being secured to a lower surface of midsole 31 and formsat least part of a ground-contacting surface of footwear 10. Outsole 32may be formed from a rubber material that provides a durable andwear-resistant surface for engaging the ground. In addition, outsole 32may also be textured to enhance the traction (i.e., friction) propertiesbetween footwear 10 and the ground. In various other configurations offootwear 10, and depending upon the manner in which midsole 31incorporates the polymer foam material, chamber 33, or both, outsole 32may be secured to the polymer foam material alone, to chamber 33 alone,or to both the polymer foam material and chamber 33. In someconfigurations, outsole 32 may be absent from footwear 10.

Chamber 33 is depicted as having a shape that fits within a perimeter ofmidsole 31 and is depicted as being primarily located in heel region 13.Accordingly, when the foot is located within upper 20, chamber 33extends under a heel area of the foot (for example, under a calcaneusbone of the wearer) in order to attenuate ground reaction forces thatare generated when sole structure 30 is compressed between the foot andthe ground during various ambulatory activities, such as running andwalking. In various other configurations, chamber 33 may extend throughalternate portions of footwear 10. For example, chamber 33 may extendonly through forefoot region 11, or only through midfoot region 12, orthrough substantially all of footwear 10 (i.e., from forefoot region 11to heel region 13 and also from lateral side 14 to medial side 15).Alternatively, chamber 33 may extend only through lateral side 14 offootwear 10, or only through medial side 15 of footwear 10. Chamber 33may also extend through any combination of regions and sides. In otherwords, in various configurations, chamber 33 may extend through anyportion or portions of footwear 10.

Chamber 33 is also depicted as being partially encapsulated withinpolymer foam material of midsole 31 and secured to the polymer foammaterial. In various other configurations of footwear 10, however,midsole 31 may otherwise incorporate chamber 33. For example, chamber 33may be substantially surrounded by or entirely encapsulated within thepolymer foam material of midsole 31, or may be above the polymer foammaterial, or may be below the polymer foam material, or may be betweenlayers or regions of one or more polymer foam materials. As an example,portions of chamber 33 may form an upper or lower surface of midsole 31.In some configurations, the polymer foam material of midsole 31 may beabsent and chamber 33 may be secured to both upper 20 and outsole 32.

Moreover, while a sidewall of midsole 31 is depicted as being formedpartially by the polymer foam material of midsole 31 and partially byportions of chamber 33, the sidewall may be otherwise formed in variousother configurations of footwear 10. For example, the sidewall ofmidsole 31 may be formed substantially entirely by the polymer foammaterial of midsole 31. In further configurations, the sidewall ofmidsole 31 may be substantially entirely formed by exposed portions ofchamber 33.

Additionally, in various configurations, chamber 33 may contact or besecured to one or more other footwear elements within midsole 31, suchas plates, moderators, lasting elements, or motion control members.Accordingly, the overall shape of chamber 33 and the manner in whichchamber 33 is incorporated into footwear 10 may vary significantly.

Furthermore, although chamber 33 is depicted and discussed as being asealed chamber within footwear 10, chamber 33 may also be a component ofa fluid system within footwear 10. More particularly, pumps, conduits,and valves may be joined with chamber 33 to provide a fluid system thatpressurizes chamber 33 with air from the exterior of footwear 10 or areservoir within footwear 10. In some configurations, chamber 33 mayincorporate a valve or other structure that permits an individual, suchas a wearer, to adjust the pressure of the fluid. As examples, chamber33 may be utilized in combination with any of the fluid systemsdisclosed in U.S. Pat. No. 7,210,249 to Passke, et al. and U.S. Pat. No.7,409,779 to Dojan, et al, including fluid systems that vary thepressure within chamber 33 depending upon, for example, the runningstyle or weight of the wearer.

Chamber Configuration

Chamber 33 is depicted individually in FIGS. 3-8C as having aconfiguration that is suitable for footwear applications. The primaryelements of chamber 33 are a barrier 40, a first bond inhibitor 45, asecond bond inhibitor 46, and a tensile element 50.

Discussion of Barrier

Barrier 40 (a) forms an exterior of chamber 33, (b) defines an interiorvoid that receives a pressurized fluid, bond inhibitors 45 and 46, andtensile element 50, and (c) provides a durable sealed barrier forretaining the pressurized fluid within chamber 33. An exterior surfaceof barrier 40 forms an outer surface of chamber 33, and an interiorsurface of barrier 40 defines the interior void. The polymer material ofbarrier 40 includes (a) a first barrier portion 41 oriented toward upper20, which may form an upper portion of barrier 40, (b) an oppositesecond barrier portion 42 oriented toward outsole 32, which may form alower portion of barrier 40, and (c) a sidewall portion 43 that extendsaround a periphery of chamber 33 and between barrier portions 41 and 42,and (d) a peripheral bond 44 that joins a periphery of first barrierportion 41 to a periphery of second barrier portion 42.

A first sheet of polymer material may be used to form first barrierportion 41, while a second sheet of polymer material may be used to formsecond barrier portion 42 and sidewall portion 43. A wide range ofpolymer materials may be utilized for barrier 40. In selecting materialsfor barrier 40, engineering properties of the materials (e.g., tensilestrength, stretch properties, fatigue characteristics, dynamic modulus,and loss tangent) as well as the ability of the materials to prevent thediffusion of the fluid contained by barrier 40 may be considered. Whenformed of thermoplastic urethane, for example, barrier 40 may have athickness of approximately 1.0 millimeter, but the thickness may rangefrom less than 0.25 to more than 2.0 millimeters, for example. Inaddition to thermoplastic urethane, examples of polymer materials thatmay be suitable for barrier 40 include polyurethane, polyester,polyester polyurethane, and polyether polyurethane. Barrier 40 may alsobe formed from a material that includes alternating layers ofthermoplastic polyurethane and ethylene-vinyl alcohol copolymer, asdisclosed in U.S. Pat. Nos. 5,713,141 and 5,952,065 to Mitchell, et al.A variation upon this material may also be utilized, wherein a centerlayer is formed of ethylene-vinyl alcohol copolymer, layers adjacent tothe center layer are formed of thermoplastic polyurethane, and outerlayers are formed of a regrind material of thermoplastic polyurethaneand ethylene-vinyl alcohol copolymer. Another suitable material forbarrier 40 is a flexible microlayer membrane that includes alternatinglayers of a gas barrier material and an elastomeric material, asdisclosed in U.S. Pat. Nos. 6,082,025 and 6,127,026 to Bonk, et al.Additional suitable materials are disclosed in U.S. Pat. Nos. 4,183,156and 4,219,945 to Rudy. Further suitable materials include thermoplasticfilms containing a crystalline material, as disclosed in U.S. Pat. Nos.4,936,029 and 5,042,176 to Rudy, and polyurethane including a polyesterpolyol, as disclosed in U.S. Pat. Nos. 6,013,340, 6,203,868, and6,321,465 to Bonk, et al.

Discussion of Tensile Element

Tensile element 50 has a configuration of a sheet or layer that islocated within the interior void of barrier 40. Tensile element 50 isalso spaced inward from sidewall portion 43 and is located between firstbond inhibitor 45 and second bond inhibitor 46. Tensile element 50extends through various first apertures 47 in first bond inhibitor 45and is secured to first barrier portion 41 in a plurality of discretefirst bond areas 55. Similarly, tensile element 50 extends throughvarious second apertures 48 in second bond inhibitor 46 and is securedto second barrier portion 42 in a plurality of discrete second bondareas 56. As discussed in greater detail below, adhesive bonding,thermal bonding, or both may be utilized to secure tensile element 50 tobarrier 40. Since apertures 47 and 48 extend across chamber 33 at anoffset with respect to each other, and since tensile element 50 issecured to barrier 40 in bond areas 55 and 56 extending throughapertures 47 and 48, bond areas 55 and 56 may in turn extend acrosstensile element 50 at an offset with respect to each other.

Tensile element 50 is unbonded or unsecured to locations on secondbarrier portion 42 opposite each first bond area 55, and tensile element50 is similarly unbonded or unsecured to locations on first barrierportion 41 opposite each second bond area 56. That is, tensile element50 is (a) secured to barrier portions 41 and 42 at various locationsacross chamber 33, and (b) spaced from barrier portion 42 or 41,respectively, at opposite locations across a thickness of chamber 33. Inturn, bond inhibitors 45 and 46 (a) may inhibit bonding between tensileelement 50 and barrier portions 41 and 42, (b) may extend acrossportions of chamber 33 in which tensile element 50 is spaced frombarrier portions 41 and 42, and (c) may be absent from portions ofchamber 33 in which tensile element 50 is secured to an interiorsurfaces of barrier portions 41 and 42, such as bond areas 55 and 56.

Each of first bond areas 55 and second bond areas 56 is substantiallysurrounded by unbonded portions 53 of tensile element 50 that are spacedfrom the interior surface of barrier 40. Accordingly, each of first bondareas 55 and second bond areas 56 is spaced across tensile element 50from the other first bond areas 55 and second bond areas 56. Unbondedportions 53 may be continuous, and may comprise substantially anentirety of tensile element 50 outside of bond areas 55 and 56. Also,unbonded portions 53 extend between first barrier portion 41 and secondbarrier portion 42 and may restrain an outward expansion of barrier 40due to a pressurized fluid within barrier 40.

First bond areas 55 may be distributed over a portion of the interiorsurface of barrier 40 formed by first barrier portion 41. That is, firstbond areas 55 may be secured to and distributed over non-continuous,isolated areas of an interior surface of first barrier portion 41, whichmay comprise less than thirty percent of an area of first barrierportion 41. Similarly, second bond areas 56 may be distributed over anopposite portion of the interior surface of barrier 40 formed by secondbarrier portion 41. That is, second bond areas 56 may be secured to anddistributed over non-continuous, isolated areas of an interior surfaceof second barrier portion 42, which may comprise less than thirtypercent of an area of second barrier portion 42.

Tensile element 50 may be a material layer that is substantially planar,sheet-like, or generally two-dimensional in its original state andbefore the pressurization of chamber 33. A variety of materials may beutilized for tensile element 50, including various textiles, polymersheets, leather, or synthetic leather, for example. Combinations ofthese materials (e.g., a polymer sheet bonded to a textile) may also beutilized for tensile element 50. Alternatively, in some configurations,tensile element 50 may be contoured in its original state and before thepressurization of chamber 33. In various configurations, tensile element50 may include a variety of materials having properties such as tensilestrength, modulus of elasticity, density, and capacity to form bonds. Inturn, each of these properties may have any of a range of values, suchas being relatively stiff, or relatively stretchable, for example.

With regard to textiles, tensile element 50 may include or may be formedfrom knitted, woven, non-woven, spacer, webbing, or mesh textilematerials or components that include rayon, nylon, polyester,polyacrylic, elastane, cotton, wool, or silk, for example. Moreover, thetextiles may be non-stretch, may exhibit one-directional stretch, or mayexhibit multi-directional stretch. More particularly, a textile materialincluded in tensile element 50 may exhibit a one-directional stretch ora two-directional stretch of at least thirty percent prior to tensilefailure. In other words, in various configurations, a material oftensile element 50 may exhibit various degrees of elasticity.Accordingly, a variety of materials are suitable for tensile element 50.

Tensile element 50 may include a polymer material, such as any of therange of polymer materials utilized for barrier 40. Tensile element 50may include, for example, a thermoplastic polymer material. In turn,bond areas 55 and 56 of tensile element 50 may be thermal bonded tobarrier 40, as described below, such that one or more thermal bonds maybe formed between first bond areas 55 and barrier 40 or between secondbond areas 56 and barrier 40. Similarly, discrete first bond areas 55and discrete second bond areas 56 may be at least partially secured tobarrier 40 by thermal bonds.

Bond areas 55 and 56 extend across tensile element 50 in two directions.For example, as incorporated within footwear 10, bond areas 55 and 56extend along tensile element 50 in a both a width or a medio-lateraldirection (i.e., a direction extending between medial side 15 andlateral side 14 of footwear 10) as well as a length or aposterior-anterior direction (i.e., a direction extending betweenforefoot region 11 and heel region 13 of footwear 10).

First bond areas 55 and second bond areas 56 also extend across tensileelement 50 in a regularly-repeating pattern. More particularly, asdepicted in FIGS. 3-8C, bond areas 55 and 56 have a configuration of aregularly-repeating pattern with seven rows and five columns. Each ofthe plurality of first bond areas 55 and the plurality of second bondareas 56 is further depicted as having a configuration of linearlyaligned groups within the regularly repeating pattern. That is, firstbond areas 55 extend across tensile element 50 and are arranged in threeof the seven rows of the regularly repeating pattern, and second bondareas 56 extend across tensile element 50 and are arranged in four ofthe seven rows of the regularly repeating pattern.

The rows of first bond areas 55 and the rows of second bond areas 56 arealso interspersed among each other across tensile element 50, such thatlinearly aligned groups of first bond areas 55 are interspersed amonglinearly aligned groups of second bond areas 56. With respect to thedirections discussed above, the rows of first bond areas 55 and the rowsof second bond areas 56 are interspersed among each other in aposterior-anterior direction. As a result, tensile member 50 mayadvantageously present minimal obstruction to at least one externalviewing angle.

The nearest bond area adjacent to each first bond areas 55 along a rowof the regularly-repeating pattern of tensile element 50 is one or moreother first bond areas 55. That is, the rows of the regularly-repeatingpattern include first bond areas 55 that are nearest neighbors to eachother along tensile element 50. With respect to the directions discussedabove, the rows include first bond areas 55 that are nearest neighborsto each other in a medio-lateral direction. In contrast, the nearestbond area adjacent to each of first bond areas 55 along the columns ofthe regularly-repeating pattern of tensile element 50 is one or moresecond bond areas 56.

In various configurations, bond areas 55 and 56 may be arranged in atleast three columns extending along the length of tensile element 50 andat least three rows across the width of tensile element 50. Furthermore,in configurations of tensile element 50 in which bond areas 55 and 56have a configuration of a regularly repeating pattern having rows andcolumns, the rows and columns of the regularly repeating pattern may beat substantially right angles to each other, as depicted in FIGS. 3-8C.In other configurations, the rows and columns of the regularly repeatingpattern may be at other than substantially right angles to each other.

As depicted in FIGS. 3-8C, each bond area 55 and 56 has a configurationof a substantially circular shape. Additionally, each bond area 55 and56 has a non-elongate shape (i.e., a two-dimensional shape with anextent in a first direction that does not exceed an extent in a seconddirection by more than a factor of two). More generally, each bond area55 and 56 may have a configuration of a convex shape (meaning that forany two points within a bond area 55 or 56, a straight line connectingthose two points is also within that bond area 55 or 56). That is, theshapes of bond areas 55 and 56 may be substantially free of outwardbulges. The substantially circular, non-elongate, convex shapes of bondareas 55 and 56 may alter one or more properties of bond areas 55 and56, such as a compactness or a configurability of bond areas 55 and 56across tensile element 50.

General Discussion of Manufacturing

A variety of processes may be utilized to manufacture chamber 33. Ingeneral, the manufacturing processes involve (a) securing a pair ofpolymer sheets, which form barrier portions 41 and 42, as well assidewall portion 43, to tensile element 50 and (b) forming a peripheralbond 44 that joins a periphery of the polymer sheets and may extendaround sidewall portion 43. Peripheral bond 44 is depicted as beingadjacent to the upper surface of chamber 33, but may be positionedbetween the upper and lower surfaces of chamber 33, or may be adjacentto the lower surface of chamber 33. The manufacturing process may also(a) locate tensile element 50 within chamber 33, and (b) secure bondareas 55 and 56 of tensile element 50 to each of barrier portions 41 and42. Although substantially all of the manufacturing process may beperformed with a mold, as described in greater detail below, each of thevarious parts or steps of the process may be performed separately informing chamber 33. That is, a variety of other methods may also beutilized to form chamber 33.

In order to facilitate bonding between barrier 40 and tensile element50, the elements of Chamber 33 may heated to soften, melt, or otherwisebegin a state change of polymer materials in one or both of barrier 40and tensile element 50. Upon contact, portions of barrier 40 and tensilemember 50 will be joined or otherwise secured, thereby forming bondareas 55 and 56 through thermal bonding. Upon cooling, therefore, thetensile member 50 will be permanently joined with barrier 40.

As utilized herein, the term “thermal bonding” or variants thereof isdefined as a securing technique between two elements (e.g., barrier 40and tensile member 50) that involves a softening or melting of athermoplastic polymer material within at least one of the elements suchthat the materials of the elements are secured to each other whencooled. Similarly, the term “thermal bond” is defined as the bond, link,or structure that joins two elements through a process that involves asoftening or melting of a thermoplastic polymer material within at leastone of the elements such that the materials of the elements are securedto each other when cooled. Thermal bonding may involve, for example, themelting or softening of thermoplastic materials within each of two ormore elements to join the elements. Accordingly, thermal bonding maycreate a polymer bond (i.e., a thermal bond between a polymer materialof one element and a polymer material of another element).

Thermal bonding does not generally involve the use of adhesives, butinvolves directly bonding elements to each other with heat. In somesituations, however, adhesives may be utilized to supplement the thermalbond or the joining of elements through thermal bonding. For example, asan alternative to thermal bonding, or in addition to thermal bonding, anadhesive, a thermally-activated adhesive, or other securing structuremay be utilized in joining the elements.

Following the manufacturing process, or as part of the manufacturingprocess, a fluid may be injected into the interior void and pressurizedbetween zero and three-hundred-fifty kilopascals (i.e., approximatelyfifty-one pounds per square inch) or more. The pressurized fluid exertsan outward force upon barrier 40, which tends to separate barrierportions 41 and 42. Tensile element 50, however, is secured to each ofbarrier portions 41 and 42 and operates to retain the intended shape ofchamber 33 when pressurized. More particularly, unbonded portions 53 oftensile element 50 extending across the interior void are placed intension by the outward force of the pressurized fluid upon barrier 40,thereby preventing barrier 40 from expanding outward and causing chamber33 to retain an intended shape. Whereas peripheral bond 44 joins thepolymer sheets to form a seal that prevents the fluid from escaping,tensile element 50 prevents barrier 40 from expanding outward orotherwise distending due to the pressure of the fluid. That is, tensileelement 50 effectively limits the expansion of chamber 33 to retain anintended shape of barrier portions 41 and 42.

Discussion of Bond Inhibitors

Although various techniques may be utilized in the general manufacturingprocess discussed above, bond inhibitors 45 and 46 prevent barrier 40and tensile element 50 from being bonded to each other, except in thelocations of bond areas 55 and 56. That is, bond inhibitors 45 and 46permit bonding in bond areas 55 and 56, while ensuring that unbondedportions 53 of tensile element 50 remain separate from and unjoined tobarrier 40.

First bond inhibitor 45 is located adjacent to an inner surface of firstbarrier portion 41, and second bond inhibitor 46 is located adjacent toan inner surface of second barrier portion 42. As depicted, bondinhibitors 45 and 46 have a configuration of sheets through which thepluralities of first apertures 47 and second apertures 48 extend,respectively. Within chamber 33, first apertures 47 may extend acrosschamber 33 at an offset with respect to second apertures 48, such thatapertures 47 and 48 may not be aligned with each other. For example,first apertures 47 may be unaligned with second apertures 48 in avertical direction.

Bond inhibitors 45 and 46 may be formed of bond-inhibiting materials,i.e., materials that are less prone to thermal bonding or other types ofbonding than various materials of barrier 40 and tensile element 50.There may be ranges of pressures and temperatures that facilitatethermal bonding between tensile element 50 and barrier 40, but will notfacilitate thermal bonding between barrier 40 and bond inhibitors 45 and46, or between bond inhibitors 45 and 46 and tensile element 50, orboth.

Although depicted as having a configuration of discrete sheets ofmaterial, bond inhibitors 45 and 46 may be integrated with one or moreof tensile element 50, first barrier portion 41, and second barrierportion 42. For example, one or more of barrier 40 and tensile element50 may include a material, concentrated at locations along a surface,which may be less prone to thermal bonding than other materials ofbarrier 40 or tensile element 50. Accordingly, during the heating andcompression of a manufacturing process, bond areas 55 or 56 maypreferentially form at locations on tensile element 50 not correspondingwith the integrated bond inhibitors.

Although chamber 33 is depicted as including two bond inhibitors 45 and46, in some configurations, chamber 33 may include other numbers of bondinhibitors. For example, in some configurations, chamber 33 may includeonly one bond inhibitor adjacent to an inner surface of first barrierportion 41 or second barrier portion 42. Alternatively, otherconfigurations of chamber 33 may include multiple discrete or otherwiseseparate bond inhibitors adjacent to the same barrier portion, such asmultiple bond inhibitors that substantially correspond in extent to asingle one of first bond inhibitor 45 or second bond inhibitor 46. Someconfigurations of chamber 33 may not include any bond inhibitors.

Discussion of Advantages

Chamber 40 has various advantages over some other types of fluid-filledchambers. For example, chamber 40 may be formed in a relativelyefficient manner from layers of material.

Manufacturing Process

Although a variety of manufacturing processes may be utilized to formchamber 33, an example of a suitable thermoforming process will now bediscussed. With reference to FIG. 9, a mold 60 that may be utilized inthe thermoforming process is depicted as including a first mold portion61 and a second mold portion 62. Mold 60 is utilized to form chamber 33from a pair of polymer sheets that are molded and bonded to define firstbarrier portion 41, second barrier portion 42, and sidewall portion 43.The thermoforming process also secures tensile element 50 within barrier40. More particularly, mold 60 (a) imparts shape to one of the polymersheets in order to form first barrier portion 41, (b) imparts shape tothe other of the polymer sheets in order to form second barrier portion42, (c) imparts shape to the polymer sheets in order to form sidewallportion 43 and to form peripheral bond 44 to join a periphery of thepolymer sheets, and (d) bonds tensile element 50 to each of barrierportions 41 and 42.

In manufacturing chamber 33, the various components of chamber 33 arelocated between mold portions 61 and 62, as depicted in FIGS. 10A and11A. In order to properly position the components, a shuttle frame orother device may be utilized. Subsequently, the various components ofchamber 33 are heated to a temperature that facilitates bonding betweenthe components. Depending upon the specific materials utilized fortensile element 50 and polymer layers 71 and 72, which form barrier 40,suitable temperatures may range from 120 to 200 degrees Celsius (248 to392 degrees Fahrenheit) or more. Various radiant heaters or otherdevices may be utilized to heat the various components of chamber 33. Insome manufacturing processes, mold 60 may be heated such that contactbetween mold 60 and the various components of chamber 33 raises thetemperature of the components to a level that facilitates bonding. Inalternate manufacturing processes, the various components of chamber 33,such as one or more of polymer layers 71 and 72, bond inhibitors 45 and46, and tensile element 50, may be heated before being located betweenmold portions 61 and 62.

Once the various components of chamber 33 are positioned and heated,mold portions 61 and 62 translate toward each other and begin to closeupon the components such that (a) first mold portion 61 contacts firstpolymer layer 71, and (b) ridge 64 of second mold portion 62 contactssecond polymer layer 72. In turn, portions of first polymer layer 71 maybe brought closer to and may be exposed to portions of tensile element50 through first apertures 47 in first bond inhibitor 45. Similarly,portions of second polymer layer 72 may be brought closer to and may beexposed to portions of tensile element 50 through second apertures 48 insecond bond inhibitor 46. The components are thus located relative tomold 60 and initial shaping and positioning has occurred.

Air may then be partially evacuated from the area around polymer layers71 and 72 through various vacuum ports in mold portions 61 and 62. Thepurpose of evacuating the air is to draw polymer layers 71 and 72 intocontact with the various contours of mold 60. This ensures that polymerlayers 71 and 72 are properly shaped in accordance with the contours ofmold 60. Note that polymer layers 71 and 72 may stretch in order toextend around tensile element 50 and into mold 60. The thickness ofpolymer layers 71 and 72 before being compressed between mold portions61 and 62 may be greater than the thickness of the correspondingportions of barrier 40 after the manufacture of chamber 33 has beencompleted. This difference between the original thicknesses of polymerlayers 71 and 72 and the resulting thickness of barrier 40 may occur asa result of the stretching taking place at this stage of thethermoforming process.

Mold portions 61 and 62 may place a specific degree of pressure upon thecomponents, thereby bonding and securing polymer layers 71 and 72 toopposite surfaces of tensile element 50. More specifically, portions offirst polymer layer 71 may be thermal bonded to portions of tensileelement 50 through first apertures 47 in first bond inhibitor 45 indiscrete and spaced areas corresponding with first bond areas 55.Similarly, portions of second polymer layer 72 may be thermal bonded toportions of tensile element 50 through second apertures 48 in secondbond inhibitor 46 in discrete and spaced areas corresponding with secondbond areas 56. Second mold portion 62 includes peripheral cavity 63 thatforms sidewall portion 43 from second polymer layer 72 at a locationspaced from a periphery of tensile element 50. As depicted in FIGS.9-11D, polymer layers 71 and 72 are thermal bonded to tensile element50, but in other manufacturing processes, polymer layers 71 and 72 maybe otherwise secured to tensile element 50. For example, polymer layers71 and 72 may be secured to tensile element 50 by an adhesive, or by useof thermoplastic threads or strips, as disclosed in U.S. Pat. No.7,070,845 to Thomas, et al.

As mold 60 closes further, first mold portion 61 and ridge 64 bond firstpolymer layer 71 to second polymer layer 72, as depicted in FIGS. 10Band 11B, thereby forming peripheral bond 44 and an interior void betweenfirst polymer layer 71 and second polymer layer 72. A periphery oftensile element 50 is spaced inward from peripheral cavity 64 and ridge64. Furthermore, portions of ridge 64 that extend away from tensileelement 50 form a bond between other areas of polymer layers 71 and 72,contributing to the formation of inflation conduit 73.

In order to provide a second means for drawing polymer layers 71 and 72into contact with the various contours of mold 60, the area betweenpolymer layers 71 and 72 and proximal to tensile element 50 may bepressurized. During a preparatory stage of this method, an injectionneedle may be located between polymer layers 71 and 72, and theinjection needle may be located such that ridge 64 envelops theinjection needle when mold 60 closes. A gas may then be ejected from theinjection needle such that polymer layers 71 and 72 engage ridge 64.Inflation conduit 73 may thereby be formed (see FIG. 10C) betweenpolymer layers 71 and 72. The gas may then pass through inflationconduit 73, thereby entering and pressurizing the area proximal totensile element 50 and between polymer layers 71 and 72. In combinationwith the vacuum, the internal pressure ensures that polymer layers 71and 72 contact the various surfaces of mold 60.

In order to facilitate bonding between tensile element 50 and barrier40, a supplemental polymer material may be added to or incorporatedwithin tensile element 50. When heated, the supplemental polymermaterial may soften, melt, or otherwise begin to change state so thatcontact with barrier portions 41 and 42 induces material from barrier 40to intermingle or otherwise join with the supplemental polymer material.Upon cooling, therefore, the supplemental polymer material may bepermanently joined with barrier 40, thereby joining tensile element 50with barrier 40. In some configurations, thermoplastic threads or stripsmay be present within tensile element 50 to facilitate bonding withbarrier 40, as disclosed, for example, in U.S. Pat. No. 7,070,845 toThomas, et al., or an adhesive may be utilized to secure barrier 40 andtensile element 50. The pressure exerted upon the components by moldportions 61 and 62 ensures that the supplemental layer or thermoplasticthreads form a bond with polymer layers 71 and 72.

When bonding is complete, mold 60 is opened and the various componentsof chamber 33 and excess portions of polymer layers 71 and 72 arepermitted to cool, as depicted in FIGS. 10C and 11C. A fluid may beinjected into the interior void through the inflation needle andinflation conduit 73. Upon exiting mold 60, tensile element 50 remainsin the compressed configuration. When chamber 33 is pressurized,however, the fluid places an outward force upon barrier 40, which tendsto separate barrier portions 41 and 42, thereby placing tensile element50 in tension. More specifically, tensile element 50 may be secured toand in contact with first polymer layer 71 in first bond areas 55, whiletensile element 50 may be secured to and in contact with second polymerlayer 72 in second bond areas 56. Upon pressurization, unbonded portions53 of tensile element 50 may extend across the interior void and may bespaced from polymer layers 71 and 72.

In addition, a sealing process is utilized to seal inflation conduit 73adjacent to chamber 33 after pressurization. The excess portions ofpolymer layers 71 and 72 are then removed, thereby completing themanufacture of chamber 33, as depicted in FIGS. 10D and 11D. As analternative, the order of inflation and removal of excess material maybe reversed. As a final step in the process, chamber 33 may be testedand then incorporated into midsole 31 of footwear 10.

Further Configurations

As depicted in FIGS. 3-8C, chamber 33 is configured to extend primarilythrough heel region 13 of footwear 10. In other configurations, chamber33 may have an alternate extent. For example, as depicted in FIG. 12A,chamber 33 may be configured to extend through substantially all offootwear 10 (i.e., from forefoot region 11 to heel region 13, and alsofrom lateral side 14 to medial side 15). Although not depicted, chamber33 may also have a shape that is incorporated into only forefoot region11 and extends under forward areas of the foot.

Although depicted in FIGS. 3-8C as extending across tensile element 50in a regularly repeating pattern having seven rows and five columns,with first bond areas 55 being arranged in three of the seven rows andsecond bond areas 56 being arranged in four of the seven rows, bondareas 55 and 56 may be otherwise configured. In various otherconfigurations, bond areas 55 and 56 may extend across tensile element50 with an alternate spacing or in alternate numbers of rows andcolumns. For example, as depicted in FIG. 12B, first bond areas 55 arearranged in three rows and three columns of a regularly repeatingpattern extending across tensile element 50. Second bond areas 56 may inturn be arranged in two rows and three columns, such that the regularlyrepeating pattern extends across tensile element 50 in a total of fiverows and three columns.

Each of bond areas 55 and 56 is depicted in FIGS. 3-8C as having aconvex, substantially circular, non-elongate shape. In otherconfigurations, any of bond areas 55 or 56 may have an alternate shape.For example, as depicted in FIG. 12C, first bond areas 55 might haveconvex shapes of ellipsoids or other non-elongate spheroids, squares, ortriangles. First bond areas 55 might also have convex shapes ofnon-elongate rectangles, hexagons, diamonds, trapezoids, other polygons,or any other regular geometric shape or irregular shape. As anotherexample, as depicted in FIG. 12D, first bond areas 55 might havenon-convex shapes such as figure-eights, laterally-compressed or pinchedsquares, or crosses. First bond areas 55 might also have non-convexshapes including polygons or any other regular geometric shape orirregular shape. Additionally, as depicted in FIGS. 12C and 12D, theshapes of first bond areas 55 may be oriented at any angle with respectto a medio-lateral direction, or with respect to a posterior-anteriordirection.

Either as an alternative to or in addition to bond inhibitors 45 and 46,bond facilitators may be incorporated into one or more of tensileelement 50, first barrier portion 41, or second barrier portion 42. Suchbond facilitators may be formed of bond-facilitating materials, i.e.,materials that are more prone to thermal bonding than various othermaterials of barrier 40 and tensile element 50. Accordingly, during theheating and compression of a manufacturing process, bond areas 55 or 56may preferentially form at locations on the surfaces of tensile element50 corresponding with the integrated bond facilitators.

As depicted in FIGS. 3-8C, each of bond areas 55 and 56 havesubstantially similar sizes. In other configurations, bond areas 55 and56 may have different or varying sizes. For example, as depicted in FIG.12E, some first bond areas 55 are larger than other first bond areas 55.Furthermore, bond areas 55 and 56 may vary in size across tensileelement 50 in a regularly repeating pattern or in any other manner,including an irregular manner.

Bond areas 55 and 56 are depicted in FIGS. 3-8C as having aconfiguration of a regularly repeating pattern. In other configurations,bond areas 55 and 56 may be otherwise distributed across tensile element50. For example, as depicted in FIG. 12F, first bond areas 55 may bedistributed across tensile element 50 in an unpatterned or otherwiseirregular manner.

In FIGS. 3-8C, bond areas 55 and 56 are also depicted as having aconfiguration of a regularly repeating pattern in which the pattern hascolumns and rows at substantially right angles to each other. Putanother way, the pattern depicted in FIGS. 3-8C corresponds with asubstantially square grid. In other configurations, bond areas 55 and 56may be otherwise patterned. For example, as depicted in FIG. 12G, thepattern of first bond areas 55 corresponds with a substantiallyhexagonal grid, whereas the pattern depicted in FIG. 13 of second bondareas 56 corresponds with a substantially diamond-shaped grid. In turn,first bond areas 55 of FIG. 12G and second bond areas 56 of FIG. 13 mayboth be distributed across tensile element 50, with first bond areas 55being spaced apart from second bond areas 56 across tensile element 50.

Additionally, the relative relationship between the height of chamber 33and the width or the length of chamber 33 may differ from the relativerelationship depicted in FIGS. 3-8C. For example, as depicted in FIG.14A, the height of chamber 33 relative to its width is greater than theheight of chamber 33 relative to its width as depicted in FIGS. 3-8C.Accordingly, in various configurations, the ratio of the height ofchamber 33 to either its width or its length may be either greater orless than as depicted in FIGS. 3-8C.

As depicted in FIGS. 3-8C, first bond inhibitor 45 is proximal to firstbarrier portion 41, and second bond inhibitor 46 is proximal to secondbarrier portion 42. However, other configurations of chamber 33 mayinclude fewer bond inhibitors. For example, in some configurations ofchamber 33, a bond inhibitor may be proximal to only one of barrierportions 41 and 42. In other configurations, such as the configurationdepicted in FIG. 14B, chamber 33 may include no bond inhibitors at all.

The spacing between bond areas 55 and 56 as depicted in FIGS. 3-8C issubstantially regular across tensile element 50. This substantiallyregular spacing may impart a substantially parallel configuration tobarrier portions 41 and 42. However, in other configurations, thespacing between bond areas 55 and 56 may impart a contour to chamber 33.For example, as depicted in FIG. 15, the spacing between bond areas 55and 56 across tensile element 50 is greater in heel region 13 than inforefoot region 11. Correspondingly, the distance between barrierportions 41 and 42 in heel region 13 is greater than the distancebetween barrier portions 41 and 42 in forefoot region 11, imparting ataper to chamber 33. Alternatively, the spacing between bond areas 55and 56 may form an indentation, or depression, or protrusion in chamber33. Differences in the spacing between bond areas 55 and 56 may impartcontours similar to those disclosed in U.S. patent application Ser. No.12/123,612 to Dua and Ser. No. 12/123,646 to Rapaport, et al.

Bond areas 55 and 56 are depicted in FIGS. 3-8C as extending acrosstensile element 50 in a regularly repeating pattern having seven rowsand five columns, of which first bond areas 55 are arranged in three ofthe seven rows and second bond areas 56 are arranged in four of theseven rows. However, in other configurations, bond areas 55 and 56 mayotherwise extend across tensile element 50. For example, as depicted inFIGS. 16-19B, both first bond areas 55 and second bond areas 56 arearranged in all seven rows and all five columns of a regularly repeatingpattern across tensile element 50. More particularly, first bond areas55 alternate in a checkerboard-like manner with second bond areas 56across tensile element 50. As a result, first bond areas 55 areinterspersed with second bond areas 56 in both a first direction (i.e.,a medio-lateral direction) and a second direction (i.e., aposterior-anterior direction).

Accordingly, when considered separately, first bond areas 55 may have aconfiguration of a first regularly repeating pattern, and second bondareas 56 may have a configuration of a second regularly repeatingpattern, and the second regularly repeating pattern may extend acrosstensile element 50 at an offset with respect to the first regularlyrepeating pattern. So configured, at least two rows of first bond areas55 may be interspersed with at least two rows of second bond areas 56across tensile element 50, and at least two columns of first bond areas55 may be interspersed with at least two columns of second bond areas 56across tensile element 50.

In the alternate configuration depicted in FIGS. 16-19B, first bondareas 55 may be interspersed with second bond areas 56 in at least twodirections. For example, first bond areas 55 may be interspersed withsecond bond areas 56 in both a medio-lateral direction and aposterior-anterior direction.

Additionally, as depicted in FIGS. 16-19B, a plurality of apertures 59in tensile element 50 extend between bond areas 55 and 56 in portions oftensile element 50 spaced from the interior surface of barrier 40, orportions of tensile element 50 not in contact with barrier 40. In somesuch configurations, due to the extent of apertures 59, unbondedportions 53 may comprise a plurality of discrete portions of tensileelement 50, each connecting a first bond area 55 to a second bond area56. In other words, tensile element 50 may have a plurality of unbondedportions 53, each unbonded portion 53 being connected at one end tofirst barrier portion 41 at a discrete first bond area 55, and beingconnected at an opposite end to second barrier portion 42 at a discretesecond bond area 56. Accordingly, tensile member 50 may advantageouslypresent minimal obstruction to at least two external viewing angles.

The invention is disclosed above and in the accompanying figures withreference to a variety of configurations. The purpose served by thedisclosure, however, is to provide an example of the various featuresand concepts related to the invention, not to limit the scope of theinvention. One skilled in the relevant art will recognize that numerousvariations and modifications may be made to the configurations describedabove without departing from the scope of the present invention, asdefined by the appended claims.

The invention claimed is:
 1. A fluid-filled chamber comprising: abarrier formed of a polymer material that defines an interior void, thebarrier having: a first portion that forms a first surface of thechamber, a second portion located opposite the first portion and forminga second surface of the chamber, and a sidewall portion that extendsbetween the first portion and the second portion to form a sidewallsurface of the chamber; a tensile element formed from a single-layersheet of material, located within the interior void, and including afirst side and a second side located on an opposite side of the samesingle-layer sheet of material than the first side, the tensile elementbeing spaced inward from the sidewall portion and being (a) secured tothe first portion of the barrier at the first side in a plurality ofdiscrete first bond areas and (b) secured to the second portion of thebarrier at the second side in a plurality of discrete second bond areas,and each of the first bond areas and second bond areas beingsubstantially surrounded by unbonded portions of the tensile element; afirst bond inhibitor disposed adjacent to the first portion of thebarrier and between the first portion and the tensile element, the firstbond inhibitor being formed from a sheet of material and including aplurality of first apertures formed therethrough at the first bondareas; and a second bond inhibitor disposed adjacent to the secondportion of the barrier and between the second portion and the tensileelement, the second bond inhibitor being formed from a sheet of materialand including a plurality of second apertures formed therethrough at thesecond bond areas.
 2. The chamber recited in claim 1, wherein firstindentations are formed at the second side of the sheet of material atthe locations of the first bond areas and second indentations are formedat the first side of the sheet of material at the locations of thesecond bond areas.
 3. The chamber recited in claim 1, wherein thetensile element includes a textile material.
 4. The chamber recited inclaim 3, wherein the textile material stretches at least thirty percentprior to tensile failure.
 5. The chamber recited in claim 1, wherein thetensile element includes a polymer material.
 6. The chamber recited inclaim 1, wherein the tensile element includes a plurality of aperturesbetween the first bond areas and the second bond areas.
 7. The chamberrecited in claim 1, wherein thermal bonds join the first bond areas tothe barrier.
 8. The chamber recited in claim 1, wherein the first bondareas are offset from the second bond areas.
 9. The chamber recited inclaim 1, wherein the first bond areas have a configuration of aregularly-repeating pattern.
 10. The chamber recited in claim 1, whereinthe first bond areas have a configuration of a plurality of rows and aplurality of columns.
 11. The chamber recited in claim 1, wherein thefirst bond areas comprise less than thirty percent of an area of thefirst portion of the barrier.
 12. The chamber recited in claim 1,wherein the tensile element includes two first bond areas that arenearest neighbors across the tensile element.
 13. The chamber recited inclaim 1, wherein the tensile element extends through the plurality offirst apertures at the first bond areas and extends through theplurality of second apertures at the second bond areas.
 14. The chamberrecited in claim 1, further including a pressurized fluid located withinthe interior void, the pressurized fluid placing areas of the tensileelement located between the first bond areas and the second bond areasin tension.
 15. A fluid-filled chamber comprising: a barrier formed of apolymer material that defines an interior void, the barrier having: afirst portion that forms a first surface of the chamber, a secondportion located opposite the first portion and forming a second surfaceof the chamber, and a sidewall portion that extends between the firstportion and the second portion to form a sidewall surface of thechamber; a tensile layer located within the interior void, the tensilelayer being spaced inward from the sidewall portion and having aconfiguration of a single-layer sheet that is secured to (a) the firstportion of the barrier in a plurality of first bond areas and (b) thesecond portion of the barrier in a plurality of second bond areas, eachof the first bond areas and second bond areas being spaced from theother first bond areas and second bond areas along both a length and awidth of the tensile layer and being formed on opposite sides of thesame single-layer sheet; a first bond inhibitor disposed adjacent to thefirst portion of the barrier and between the first portion and thetensile layer, the first bond inhibitor being formed from a sheet ofmaterial and including a plurality of first apertures formedtherethrough at the first bond areas; and a second bond inhibitordisposed adjacent to the second portion of the barrier and between thesecond portion and the tensile layer, the second bond inhibitor beingformed from a sheet of material and including a plurality of secondapertures formed therethrough at the second bond areas.
 16. The chamberrecited in claim 15, wherein the tensile layer includes a plurality ofapertures between the first bond areas and the second bond areas. 17.The chamber recited in claim 15, wherein the tensile layer includes twofirst bond areas that are nearest neighbors across the tensile layer.18. The chamber recited in claim 15, wherein thermal bonds join thefirst bond areas to the first portion of the barrier.
 19. The chamberrecited in claim 15, wherein the first bond areas are offset from thesecond bond areas.
 20. The chamber recited in claim 15, wherein thefirst bond areas have a configuration of a regularly-repeating pattern.21. The chamber recited in claim 20, wherein the regularly-repeatingpattern has at least three rows extending along the width and at leastthree columns extending along the length.
 22. The chamber recited inclaim 15, wherein the plurality of first bond areas is interspersed withthe plurality of second bond areas in both a first direction and asecond direction.
 23. A fluid-filled chamber comprising: a barrierformed of a polymer material that defines an interior void; a bondinhibitor located adjacent to an inner surface of the barrier and havinga first plurality of apertures, the bond inhibitor being formed from asheet of material; an additional bond inhibitor located adjacent to anadditional inner surface, the additional bond inhibitor formed from asheet of material and including a second plurality of apertures; atensile layer formed from a single-layer sheet of material and locatedwithin the interior void between the bond inhibitor and the additionalbond inhibitor, the tensile layer being spaced inward from a peripheryof the barrier, being secured to the barrier at a plurality of bondedareas, extending through the first plurality of apertures and the secondplurality of apertures at the plurality of bonded areas, and having anunbonded area substantially surrounding each of the bonded areas, theplurality of bonded areas including first bonded areas and second bondedareas that are formed on opposite sides of the same single-layer sheetof the tensile layer; and a fluid located within the interior void, thefluid being pressurized to place the unbonded area of the tensileelement in tension.
 24. The chamber recited in claim 23, wherein atleast one of the first bonded areas and the second bonded areas includesa substantially circular shape.
 25. The chamber recited in claim 23,wherein the tensile layer includes a textile material.
 26. The chamberrecited in claim 23, wherein the tensile layer includes a polymermaterial.
 27. The chamber recited in claim 23, wherein the tensile layerincludes a plurality of apertures between the bonded areas.
 28. Thechamber recited in claim 23, wherein thermal bonds join the bonded areasto the barrier.
 29. The chamber recited in claim 23, wherein the bondedareas have a configuration of a regularly-repeating pattern.
 30. Thechamber recited in claim 23, wherein each of the bonded areas has aconvex, non-elongate shape.
 31. The chamber recited in claim 23, whereinthe bond inhibitor corresponds with a portion of the unbonded area.